Chestnuts growing fast

I planted two grafted chestnut trees in Jan 2019. One silverleaf and one Marron Di Val Di Susa. I have to admit I’m surprised how fast they’re growing this year. The marron already has probably 7ft of growth this year. Is this normal for young chestnut trees? It’s growing so fast that it grew around the metal wire tag I had on it. I used some pliers to pull it out and place it a lot higher up. Each tree is surrounded by goumi bushes. I’ve also fertilized them a few times in the spring with diluted urine. Anyways I’m just impressed at this growth speed. It’s far higher than anything else in my food forest

What species or hybrids are they?  I don't have any great insight but am super interested in chestnuts, so I'd like to understand how different species and varietals are growing in different climates. It seems in Portland that maybe American would struggle with the dry summers, but that Chinese wouldn't, but that's just a guess.  Obviously the dry summers would probably help with avoiding the blight, but I guess there are always tradeoffs.

not familiar with the varieties you mention but dustan are a very fast growing chestnut.  I've got a bunch of trees that are a couple years old and this year they easily put on that much growth. once a tree gets established and conditions are good and its happy it will take off in growth. history tells us that chestnut trees in North America were well over 100' tall and in Appalachians 25% of trees were chestnuts

They're Japanese/European hybrids I believe. The Marron is castanea sativa. The silver leaf is more of a Japanese heavy hybrid castanea crenata. They don't seem to mind our dry summers at all. Most of my trees shut down once the dry really starts setting in but the chestnuts, figs and olives just continue growing like it's nothing. Pretty cool!